SLVSDV8 July 2017 TPS54424
The device uses an adjustable fixed frequency, peak current mode control. The output voltage is compared through external resistors on the FB pin to an internal voltage reference by an error amplifier which drives the COMP pin. An internal oscillator initiates the turn on of the high-side power switch. The error amplifier output is converted into a current reference which compares to the high-side power switch current. When the power switch current reaches current reference generated by the COMP voltage level the high-side power switch is turned off and the low-side power switch is turned on.
The device adds an internal slope compensation ramp to prevent subharmonic oscillations. The peak inductor current limit remains constant over the full duty cycle range.